Preheat oven to 180ºC/350ºF. Place garlic cloves on a chopping board and using the palm of your hand or the blade of a knife smashed them to split. Mix the fat, the Spanish extra virgin olive oil and the splinted garlic cloves in an ovenproof frying pan and heat at moderate temperature until the fat melts.
Add the onion and sauté until tender and golden brown, about 20 minutes. If onion cooks to fast, add one tablespoon of water to slow down the process. Add the potatoes slices, one teaspoon of salt and one rosemary sprig. Remove with a spoon to make sure that potato slices get well covered with the olive oil.
Place the frying pan in the oven and bake during 20 minutes. Remove from the oven, pour in the wine and place again in the oven and bake for another 10 minutes until alcohol evaporates.
Remove frying pan from the oven and place the mushrooms on top of the potatoes and the onion mixture. Pour in the chicken stock and with a spoon, pour some of the cooking liquid over the mushrooms. Place again in the oven the frying pan and bake for 15 minutes more.
Preparation: Sonia Fuentes/©ICEX.